The invention relates to a low profile connector for electrical components and, more particularly, to an integrated circuit connector having contacts press fitted into a substrate and a layover insulator.
Prior art component connectors have generally been of the type wherein contacts are either loaded down into receiving openings in the top of an insulator or wherein contacts are held in a fixed array and the insulator molded around the contacts. In either case, the manufacture of such connectors is a time-consuming, relatively expensive process. Further, the contacts used in prior art component connectors are either generally planar with one or two bowed lead gripping surfaces or are cylindrical, screw machined parts which are expensive both to manufacture and to mount in an insulative housing.
Certain prior art contacts must include transverse shoulder portions which contribute to the overall length thereof and, consequently produce a higher profile connector. When such shouldered contacts are mounted on relatively close centers, the spacing between adjacent contacts may also be quite crowded. The improved contact used in the connector of the present invention is generally shorter than prior art contacts, is adapted to close spacing without excess crowding between adjacent contacts and includes a highly reliable gripping socket portion for retaining the leads of a component.
Prior art integrated circuit connectors have been proposed wherein generally planar contacts having transverse shoulders are press fitted into parallel adjacent rows of holes in a substrate and then separated by insulative strips. For examples in U.S. Pat. No. 3,624,586 to F. T. Inacker entitled Integrated Circuit Connector System and assigned to the assignee of the present application, there is shown such a system for connecting dual inline integrated circuit packages in a "dead bug" configuration, i.e. where the component leads extend upwardly. However, for certain applications it is preferable to mount dual inline integrated circuit components in a "live bug" configuration, i.e. with the component leads extending downwardly and, further, to, provide a live bug connector having a relatively low profile and contacts which are arranged in a closely spaced array with more spacing, and consequently less crowding, between adjacent contacts than with prior art shouldered contacts.
Generally, prior art press fitted contacts have included a solid press fitting neck section having angular edges to slightly deform the walls of the hole and form a tight frictional fit therewith. Certain prior art connector contacts have relied upon a transverse shoulder as a gripping surface for press fitting the contact down into an aperature. Other contacts are press fitted by pulling them through an aperture by the tails from the opposite side to avoid either inclusion of a press fit shoulder or applying force directly to a delicate top portion of the contact. A hollow folded contact having a sturdy socket portion at the top is used in the connector and method of the present invention and is especially adapted for press fitting into cylindrical holes in a substrate by a force applied directly to the top of the contact.
The contact used in the present invention is described and claimed in copending patent application Ser. No. 460,932, filed by J. Preston Ammon on Apr. 15, 1974, entitled "Folded Electrical Contact" and assigned to the assignee of the present invention. The preferred embodiment of the contact includes a lead receiving socket portion and a press-fitting central portion, both of which are preferably formed with planar side walls and are generally rectangular in cross-section and open down the center. The lead receiving socket portion is received up into a recess in a layover insulative housing while the press fitting central portion includes a plurality of longitudinally extending planar surfaces joined by angular edges which engage and slightly deform the material forming the walls of the hole. When press fitted, the planar surfaces of the press fitting central portion of the contact are bowed slightly outwardly to resiliently urge parts of the contact outwardly against the walls of the hole and produce a highly reliable frictional engagement therewith.